On Irradiance Measurement Errors at Sea Due to Tilt of Pyranometers

摘要: Abstract Calculations are made of errors in the measurement solar irradiance at sea surface. which occur when pyranometers tilled. Tilts due to buoy or ship motion caused by wave action a preferential tilt drag considered. Errors depend on sky condition and maximum for clear skies. They soar zenith angle relative azimuth sun directions, vary, therefore, with latitude season time day. as large ±10% ±20% daily average (with sign dependent tilt) could be encountered skies poleward 45°N S winter half year 10° tilt. Instantaneous can large. Because difficulty making corrections posteriori, gimbal mounting is recommended.